Roadway construction material and an additive therefor



United States Patent ROADWAY CONSTRUCTIUN MATERIAL AND AN ADDITIVE THEREFOR Lowell T. Crews, Homewood, and Mathew L. Kalinowski,

Chicago, 11]., assignors to Standard Oil Company, Chicago, Ill., a corporation of Indiana No Drawing. Application August 9, 1954 Serial No. 448,774

8 Claims. (Cl. 106-273) The present invention is directed to improvements in bitumen compositions, and particularly to improvements "in mineral aggregate coating compositions, and more particularly relates to bitumen compositions having improved adherence to damp or wet mineral aggregates, and to improvements in the method of making such compositions.

Residual oils and/ or bituminous materials used in the preparation of pavements and roads do not coat and.

adhere well to mineral aggregates unless the aggregate is substantially dry, and for this reason, in conventional pavements or road construction practice, it is customary to dry the mineral aggregate by suitable well known methods. Furthermore, water entering the road or pavement during service may have a detrimental effect in that it may displace the oil or bitumen from the surface of the aggregate and thus diminish the bonding effect of the oil and/or bitumen. This materially shortens the life of the road or pavement requiring frequent repairs and is, therefore, uneconomical.

Mineral aggregates employed in road or pavement construction range in character from hydrophilic to hydrophobic. In general, siliceous and acidic minerals, such as sands and gravels, tend to be hydrophobic, while calcareous alkaline minerals, such as limestone, tend to be hydrophilic. It has been observed that the mineral aggregates appear to have a greater attraction for water than for oil or bitumens and that it is difficult to obtain, by conventional methods, complete or satisfactory coating of aggregates by oil or bitumen when Water is present. Furthermore, even though satisfactory coating is obtained by using dry aggregate, the oil or bitumen tends to be displaced if Water enters the pavement or road.

It is known that the coating of damp or wet mineral aggregates by oil or bitumen may be effected and the resistance of the coating to displacement or stripping by water improved by treating the aggregate with small amounts of a water-soluble soap of a fatty acid in conjunction with a water-soluble salt of a polyvalent heavy metal or activator. For optimum results with these reagents, the relative amounts of the two reagents must be carefully adjusted. Thus, when a divalent heavy metal is used as activator, the amount of soap used should be substantially one mole per mole of activator; with a trivalent metal, between one and two moles of soap per mole of activator. Use of larger amounts of soap than this diminishes the effect obtained, and this diminution of effect increases with excess of soap over the proportions given until, when the amount of soap becomes equivalent to the activator, i.'e., two moles of soap per mole of divalent metal or three per mole of trivalent metal, the beneficial effect of the reagent substantially disappears.

The above method has the disadvantage that the relative amounts of soap and polyvalent heavy metal activator are critical and must be carefully adjusted for optimum results. Use of an excess of soap over the optimum amount diminishes rather than enhances the effect obtained; the use of excess heavy metal to avoid the danger of excess soap is not harmful but increases the cost. Furthermore, the two reagents must be Weighed or measured out and added to each batch, as neither is soluble in the oil or bitumen; while this disadvantage may be partially overcome under favorable conditions by using, in place of the soap, a fatty acid dissolved in the oil or bitumen, this expedient is effective only under favorable conditions of low moisture content of the aggregate, adequate and efficient mixing, etc. Under conditions which are not at all severe, such as appreciable amounts of water andlor facilities for only moderately efliclent mixing, fatty acids appear not to be sufficiently soluble in water to reach and react with the heavy :metal ion to the required extent, and if added directly to'the mixture or dissolved in theoil or bitumen, are practically Without effect.

Another important disadvantage of the above method is that a heavy polyvalent metal salt must be used with the soap. Furthermore, it has been found that while some limestoncs appear capable of adsorbing or reacting with polyvalent heavy metal ions and accordingly respond to some degree to the above method, a great many others -do not, and with these it is dilficult or impossible to obtain a good coating by the above method. .Also, since the foregoing method is not in general satisfactory with limestone, a great many natural mixed aggregates such as gravels containing both siliceous and calcareous particles will have only a portion of the particles coated.

In addition to the use of polyvalent fatty acid soaps in bitumens as mineral aggregate coating agents, certain organic nitrogen compounds, such as those obtained by reacting a polyarnine with a fatty acid under conditions to form essentially amid-es, have been use-d for thi purpose. However, although amide-amine type asphalt additives are effective coating agents for acidic mineral aggregates complete amidation of amine soaps of carboxyl-ic acids such as that produced by high temperature treatment of a fatty acid affording material with an amine results in the production of a bitumen additive with reduced effectiveness for the coating of acidic mineral aggregates such as sand and gravel. It is a primary object of this invention to avoid the formation of .amides in the preparation of the fatty acid-amine type additive for bitumens and thereby retain the effectiveness of the additive in fortifying the coating vmaterial for application to acidic aggregates. Another object of the present invention is to provide a coating composition for acidic and alkaline mineral aggregates which will ,not be stripped therefrom by aqueous liquids. ,Still another object of the invention is to provide a coating composition for acidic and alkaline mineral aggregates which can be supplied without the necessity of drying the mineral aggregate and which will adhere thereto even in a wet condition. Another object of the invention is to avoid the production of a preponderance .ofqamido groups in the fabrication of fatty acid-amine type bitumen additives. Still another object of the invention is to produce a heat-stable fatty acid-amine type bitumen additive. A further object is to produce a bitumen additive of sufficiently low viscosity to be pumpable at ambient .temperatures, thus to facilitate transfer of the additive and to facilitate the incorporation thereof in bitumen materials.

In accordance with the present invention, bitumens, such as'for example, road oils and asp'halts having improved mineral aggregate coating properties, especially with respect to Wet acidic and alkaline mineral aggregates, are obtained by incorporating in such bitumens from about 0.25% to about 5%, and preferably from about 0.5% to about 3%,"by weight, based on the bitumen, of

3 i the product obtained by reacting a mixture of aliphatic amines consisting essentially of at least 75%, that is, from about 75% to about 95%, by weight, of at least one alkylene polyamine having from 2 to 6 amino groups and having from 2 to about 20 carbon atoms per molecule and having at least one primary amino group per molecule and from about to about 25%, by weight, of at least one alkanol monoamine, with the propane-insoluble fraction obtained in the propane extraction of crude fatty materials, such as animal, marine and vegetable fats, fatty oils or fatty acids split therefrom, under conditions which avoid the formation of amides so that a product essentially free of amido groups is obtained. Since amidation of amine soaps is brought about by the loss of water at high temperatures, the reaction of the aliphatic polyamine-alkanol monoamine mixture with the aforementioned propane-insoluble fraction is carried out at temperatures below about 240 F., that is, in the range of from about 180 F. to about 240 F., preferably from about 200 F. to about 230 F. for a period of time not longer than about 0.25 to 1.0 hour. An excess of the mixed polyamines over the stoichiometric requirement for reaction with the propane-insoluble fraction is used. Thus, in general, from about 5% to about 50% excess of polyamine-alkanol amine mixture is desirable. The term alkanol amine, as used in this specification and the claims, is defined as monoamines containing at least one alkanol substituent attached to the nitrogen atom, the remaining substituents attached to the nitrogen atom being selected from the class of alkyl, alkanol, and hydrogen.

The reaction product of the propane-insoluble material with the mixed amines, when diluted with a hydrocarbon oil, preferably an aromatic hydrocarbon-rich hydrocarbon oil in an amount of from about 10% to about 200% based on the weight of the reaction product, provides a concentrate of the reaction product which is pumpable at ambient temperatures, thus making possible the transfer of the additive product and dispersion thereof in bitumen coating material at ambient temperatures and thus avoiding the necessity of lowering the viscosity thereof by heating. Hence, amide formation is thereby minimzed in handling the additive. On the other hand, reaction products of the propane-insoluble fatty acid affording material with either alkylene polyamine alone or with the alkanol monoamine alone even when diluted with an aromatic hydrocarbon-rich hydrocarbon oil at a 1:1 ratio of diluent to reaction product is too viscous to pump and approaches a semi-solid with respect to consistency.

The propane-insoluble fraction obtained in the propane extraction of crude fatty materials of the type above described contains, in addition to fats and fatty acids, esters of fatty acids and sterols. These propane-insoluble fractions which are obtained as residue of the order of about 0.2% to about 10%, by weight, contain most of the color bodies which are present in the crude fatty materials, and because of their very dark color, are referred to in commerce as Ebony Fats. The properties of representative samples of the propane-insoluble residues obtained from animal fats and from vegetable oils, on a water-free basis, are approximately as follows:

Residue Residue Property from from Animal Vegetable Fat Oil Viscosity, Seconds Saybolt at 100 F 6500 930 Viscosity, Seconds Saybolt at 130 F 1860 430 Viscosity, Seconds Sa-ybolt at 210 F 300 100 Ash, Weight Percent 1. 3 .06 A. P. I. Gravity. degrecs 10 16 Acidity '1. 5. T. M. (ID-664) IV 41 63 Pentium Insoluble, Weight Percent 2.6 4.2 Benzene Insoluble, Weight Percent 7 1. 0 Saponification Number 190 170 Fatty Acid 20 31 Iodine Number 58 106 The above properties are, of course, merely illustrative,

had an equivalent weight of 488.

and it should be understood that both the amount and the property of the propane-insoluble residues depend upon the nature of the crude fatty material extracted and upon the particular conditions employed in effecting the extractive fractionation. The Ebony Fat employed in the examples described below is known commercialy as Hodag (#3) Process Fat supplied by Hodag Chemical Company. This product is obtained by propane precipitation of a vegetable oil. The Hodag (#3) Process Fat The term crude as used herein means that the color bodies and other materials, insoluble in 6 to 30 volumes of the propane at about F. to about F. have not been removed regardless of whether or not the fatty material has been destearinized.

The method of fractionating the animal, marine and Vegetable fatty materials with propane to obtain Ebony Fat is well known to those skilled in the art and one example thereof is commonly referred to as the Solexol Process, currently and commercially used and described in Industrial and Engineering Chemistry of February 1949, page 280. The system for effecting such extractive fractionation is described in detail in U. S. 2,505,338, and

U. S. 2,521,234. For most crude animal fats, marine oils and vegetable oils, and similar fatty materials including acids split from such fats, the fractionation conditions are employed which give a propane-insoluble residue of about 1%, i. e., about 0.2% to about 2%, although in some cases such residues may be as large as 5% or even 10%.

The major part, that is, at least 75% by weight, of the polyamine reactant employed in preparing the additive of the present invention is an aliphatic polyamine, particularly an alkylene polyamine containing at least one and preferably more than one primary amino nitrogen atom. Examples of such alkylene polyamines suitable for the here-in-described purpose are ethylene diamine, propylene diamine, diethylene triamine, diamylene triamine, triethylene tetramine, tripropylene tetramine, diethylene propylene tetramine, tetraethylene pentamine, tetrabutylene pentamine, diethylene dipropylene pentamine, butylene diamine, dihexylene triamine, and the like, or mixtures thereof. For example, a suitable polyamine product as the major polyamine component of the polyamine alkanol amine mixed reactant is a crude diethylene triamine containing minor amounts of ethylene diamine and triethylene tetramine. Other suitable polyamines include those having the general formula RNH (CH NH in which R is preferably a C to C aliphatic chain, and whichare obtained by condensing the suitable amine with acrylonitrile and hydrogenating to the corresponding diamine. Commercially available polyamines of this type are those marketed by Armour and Company as Duomeens, which are prepared by the condensation of a dodecyl (coco) amine or an octadecyl' (tallow) amine with acrylonitrile, followed by hydrogenation to the corresponding diamine product; these products are marketed as Duomeen C and Duomeen T, respectively.

The alkanol amine components of the amine reactants are mono-, diand tri-substituted alkanol monoamines, preferably the dior tri-substituted alkanol monoamines such as triethanol amine. The alkanol substituents groups may contain from 2 to 4 carbon atoms per substitnent group. Examples are monoethanol amine, diethanol amine, triethanol amine, monoethyl ethanol amine, diethyl ethanol amine, the propanol amines and the butanol amines. Particularly suitable as the alkanol monoamine component is triethanol amine. Mixtures of the above alkanol amines may be used as the alkanol amine component of the reaction mixture.

In the preparation of the Ebony Fat and polyaminealkanol amine reaction product, it is preferable, although not essential, that the Ebony Fat be. first dehydrated to obtain an essentially water-free product, or a product having not more than about 0.5% water. This can be readily accomplished by diluting the Ebony Fat with from about to about 200% of a suitable hydrocarbon solvent, preferably a solvent rich in aromatic hydrocarbons, and by heating the diluted mixture at a temperature of about 210 F. to 290 F. while stirring and/ or blowing with air or other suitable gaseous medium until the water content has been reduced to the desired value. Following the dehydration step the Ebony Fat-oil mixture is cooled to a temperature below about 150 F., preferably by the continued inert gas blow such as for example a passage therethrough of cold air. If the Ebony Fat contains an undesirable amount of contaminants, they can be removed by permitting the hot dehydrated solution to settle, and decanting the diluted solution of purified Ebony Fat. If desired, the diluent may be removed from the dehydrated Ebony Fat by suitable means, such as by distillation under vacuum; however, we prefer to react the diluted Ebony Fats with the mixed amines.

Aromatic-rich hydrocarbon solvents suitable for this purpose are preferably those having boiling points above about 220 F. at atmospheric pressure, for example, from about 220 F. to about 600 F., and includes mononuclear aromatic hydrocarbons or condensed ring aromatics, such as naphthalenes and mixtures of the higher boiling mono-nuclear aromatic hydrocarbons and polynuclear aromatic hydrocarbons.

A preferred source of mixed aromatic hydrocarbons, suitable for the purpose, is a light catalytic cycle stock obtained from a powdered or a fluid-type catalytic-type hydrocarbon cracking operation in which gas oil or heavier hydrocarbons are cracked at a temperature of 800 F. to 1050 F. under a pressure of about atmospheric to 50 pounds per square inch, in the presence of suitable fluid or powdered catalyst, such as for example silica-alumina, silica-magnesia, and other well-known cracking catalysts. A method of conducting a fluidized cracking operation is described in U. S. 2,341,193 issued to Fred W. Scheineman, February 8, 1944. Fractions from the process heavier than gasoline, depending upon their boiling range, are commonly referred to as light catalytic cycle stock,-heavy catalytic cycle stock and catalytic recycle resid, which usually are cycled to cracking. A light catalytic cycle stock particularly well suited as a diluent for the dehydration of the Ebony Fat is a fraction having an aromatic content of at least about 40% and a distillation range between about 425 F. and 560 F. A typical analysis of a'suitable light catalytic cycle stock shows the material to be composed substantially of about 10% normal C to C parafiins, about 45% of other paraffins, and naphthenes, about 5% mono-nuclear aromatics, which are mainly monoand hexa-alkylated benzenes, and about 40% polynuclear aromatics, which are mainly alkyl naphthalenes, largely methylated naphthalenes. While we prefer to use a light catalytic cycle stock of the type described, hydrocarbon fractions from other catalytic conversion processes or thermal hydrocarbon conversion processes are suitable, provided they have an aromatic content of at least about 20%, and a distillation range of above about 220 F. If desired, a part of the bitumen coating material, if a road oil, may be used as diluent for the Ebony Fat for the dehydrating operation.

The dehydrated Ebony Fat, preferably but not necessarily in solution in the light catalytic cycle stock or other suitable diluent, is reacted with the polyamines in the ratio by weight of from about 20:1 to about 5:1, and preferably in a ratio of from about 12:1 to about 5 :1 Ebony Fat to the polyamine-alkanol amine mixture at a temperature below about 240 F. and preferably from about 200 F. to about 230 F., for not more than about one hour. If desired, the mixture of amines may be added to the Ebony Fat in the form of a dispersion Ebony Fat, as indicated in the table.

in a hydrocarbon oil. By conducting the reaction in the manner herein described, an effective stable coating agent additive essentially free of amido groups is obtained.

The Ebony Fat -amine reaction product samples, the performance of which as additives in liquid asphalt, that is, cutback asphalt of the type described hereinbelow, is shown in the table, were prepared as follows:

To a mixture containing an equivalent weight of Ebony Fat, that is, Hodag (#3) Process Fat, dispersed in light catalytic cycle stock was added the amine or mixture of amines, that is, mixture of alkylene polyamine with alkanol monoamine and additional light catalytic cycle stock was added to provide a 50% (by weight) light catalytic cycle stock-50% (by weight) reactant mixture, that is, a diluted reaction mixture. This reaction mixture was heated in a primary heating step at a temperature of 230 F. for a period of 60 minutes, contact of the reactants being obtained by vigorous stirring of the diluted reaction mixture. The ratio of total amines to Ebony Fat added to the Ebony Fat to make up ,the' reaction mixtures was, for all examples tabulated below, 1% equivalents of total amines per equivalent of Following the primary heating step, the reaction mixture was divided, a part being added to the liquid asphalt and the asphalt was subjected to aggregate coating tests as described hereinbelow. The results of the coating tests are given as Examples 1, 3, 5, 7, and 9 in the table. Aliquots of the diluted reaction products which had been prepared at 230 F. were then given a secondary heat treatment at 300 F. for a period of 45 minutes after which they were incorporated in the liquid asphalt samples and these asphalt samples so fortified were tested for coating efficiency todetermine the effect of the secondary heating on coating of the aggregate. The results are tabulated below as performance of Examples 2, 4, 6', 8, and 10. The concentration of reaction product used in the asphalt was 1.0% by weight, that is, 2.0% by weight of the diluted product based on the weight of the asphalt in making the tests.

The viscosities of 100% light catalytic cycle stock diluted reaction product of the 1 eqivalent of Ebony Fat with 1% equivalents of ethylene diamine as the sole amine reactant was 393 (Furol at F.) whereas the viscosity of the like diluted reaction product of the 1 equivalent Ebony Fat with a mixture consisting of 1% equivalents of ethylene diamine and /8 equivalent of triethanolamine was only 250 (Furol at 140 F.). Thus the latter reac tion product was much less viscous and was of a consistency to be pumpable at ambient temperatures while the former reaction product was not of satisfactory consistency to be so handled. In general, the consistency of the reaction products of the Ebony Fat with the alkylene polyamine-alkanolamine mixture was more fluid than reaction products of the Ebony Fat with alkylene polyamine or with alkanol amines as the sole amine reactant.

While we have not been able to determinedefinitely the composition of the reaction product of the Ebony Fat with the mixed alkylene polyamine-alkanolamine, we believe the reaction product consists essentially of the amine soaps of the fatty acids contained in the Ebony .Fat, together with unreacted esters and alcohols, i. e., sterols.

The asphalt component of the herein described composition may be any bitumen which is useful for the coating of mineral aggregates used in the making of roads, highways, etc., or for the coating of other materials or surfaces where a water-resistant bond between the surface and the asphalt is advantageous or necessary. The term asphalt as employed herein is intended to be synonymous with bitumen and to cover a liquid, semi-solid, or solid plastic bituminous material of the type employed in making or surfacing of highways and/ or pavements, caulking agents, sealing compounds, water impervious paints, roofing materials, etc. Such asphalt or bituminous materials are mixtures of hydrocarbons of natural pyrogenous origin, and are usually derived from petroleum or coal but may occur as such in nature. Asphalts may be derived as distillation residues or cracking residues with or without oxidation by air-blowing or by catalytic oxidation. A specific example of a liquid asphalt of the type commonly employed in the preparation of highways, etc., is a petroleum residuum fluxed with a light aromatic diluent boil- 55 the above described type and is designated as MC2 grade. This test is designated as the Modified Colorado Coating Test. A coating of 80% in this test is considered adequate coating efiiciency to satisfy the most severe service requirements for the coating of wet aggregates with bitumen material.

The results of the tests are tabulated below. The asphalt coating agent was a liquid asphalt, that is, a cut-back. asphalt of the above type designated as medium curing-2 mg in the range of 400 F. to 700 F. to give a cut-back 10 grade.

Table "Ebony Trietha- Thermal Percent Coating Fat Ethylene Monoethan01 Process- Exatnple Equiv- Diamine n01 Amine Amine ing, de-

alents (Equivs) (Equivs) (Equiv.) grees Sand Limestone product of the following specifications:

Cutback asphalt 1 Not less than. 1 Not more than.

Normally solid paving asphalts of the 40 to 200 penetration grades commonly used in road building fall within the following specifications:

Penetration at 77 F 40-200.

ASTM ductility at 77 F Not less than 100. Oliensis spot test Negative.

Solubility in CCl' percent- Not less than 99.5. Specific gravity at 60 F Not less than 0.990l.000. Flash, F. (C. O. -C.) Not less than 475.

Loss on heating 50 grams for 5 hours at 325 F., percent Penetration of residue at 77 F., percent of original penetration a- Not less than 70-75.

The effectiveness of the-herein described Ebony Fatmixed polyamine-alkanolamine reaction products in enhancing the adhesion of asphalts to wet mineral aggregates is determined by subjecting blends of asphalts and the described reaction products to the following test.

In preparing the samples of asphalt for testing the coating efficiency of the fortified asphalt samples, diluted additive prepared in the above examples suflicient to provide 1.0% (by weight) concentration of active Ebony Fat-amine component in the asphalt was mixed thoroughly with the asphalt. Twenty grams of Ottawa sand and grams of 20 to 35 mesh limestone were separately weighed into 2-oz. containers and covered with one-half inch of distilled water. One gram of the asphalt con taining 1% of the additive was floated on the water. The mixture Was shaken for seconds and the extent of coating was determined by visual inspection. The asphalt used in these tests was a liquid medium curing asphalt of Not more than 0.5.

The results in the table show the superiority of the asphalt containing the Ebony Fat-mixed amine reaction products. Thus secondary heating to 300 F. caused the coating efliciency (on sand) of the liquid asphalt fortified with Ebony Fat-ethylene diamine reaction product, so heated, to decrease from 95% to 50% (Examples 1 and 2). However, when Ms equivalent of the ethylene diamine was replaced by equivalent of triethanol amine in the reaction mixture such secondary heating resulted in a decrease in coating efiiiciency on sand of only 5%, that is, 95% to coating efliciency (Examples 1 and 2 versus 9 and 10). Improvement was also realized when monoethanol amine was substituted for a part of the ethylene diamine (Example 2 versus Example 8).

Having thus described our invention, we claim:

1. An additive practically free of amido groups suitable for use in bitumen coating material, prepared by reacting for a period of from about A to about 1.0 hour at a temperature within the range of'from about 180 F. to about 240 F. a mixture of alkanol monoamines and alkylene polyamines having from 2 to about 6 amino groups per polyamine molecule, said mixture consisting essentially of from about 75% to about by weight of at least one alkylene polyamine containing at least one primary amino group and from about 5% to about 25% by weight of at least one alkanol monoamine, the alkanol groups of which contain from 2 to 4 carbon atoms, with substantially dehydrated Ebony Fat, the total of amines plus alkylolamines contacted with said Ebony Fat being in excess of the stoichiometric requirement for reaction with said Ebony Fat.

2. The product as described in claim 1 wherein the Ebony Fat is dehydrated to a water content of not more than about 0.5% by heating with agitation in the presence of an aromatic-rich hydrocarbon oil diluent prior to contact with the amine components of the reaction mixture.

3. The product as described in claim 1 wherein the reaction of the Ebony Fat with the mixture of alkylene polyamine and alkanol monoamine is carried out in the presence of an aromatic-rich hydrocarbon oil diluent.

4. The product as described in claim 1 wherein the use as a bitumen additive, prepared by forming a homogeneous mixture of Ebony Fat in an aromatic hydrocarbon-rich hydrocarbon solvent boiling in the range of from about 220 F. to about 600 F., dehydrating said mixture to a Water content of less than about 0.5% based on the Ebony Fat content of said mixture, reacting a mixture of amines consisting essentially of from about 75% to about 95% of at least one alkylene polyamine having from 2 to 6 amino groups per molecule, at least one of which is a primary amino group and from about 5% to about 25% of at least one alkanol monoamine having from 2 to 4 carbon atoms per alkanol group per molecule of said alkanol monoamine, with the Ebony Fat in the dehydrated mixture of Ebony Fat and hydrocarbon oil at a temperature within the range of about 180 F. to about 240 F., for a period of from about hour to about 1.0 hour, the total of amines plus alkylolamines reacted with said Ebony Fat being in excess of the stoichiometric requirement for reaction With the Ebony Fat.

7. A bitumen composition comprising a major propoi tion of a bitumen and from 0.25% to about 5% of the hydrocarbon oil-diluted reaction product of claim 6.

8. A roadway construction material comprising mineral aggregate admixed With a coating composition consisting essentially of a major proportion of a normally liquid bitumen and from about 0.25% to about 5.0% of the heat-stable reaction product of claim 1.

References Cited in the file of this patent UNITED STATES PATENTS 2,344,260 Morgan et a1 Mar. 14, 1944 2,386,867 Johnson Oct. 16, 1945 2,438,318 Johnson Mar. 23, 1948 2,521,234 Leaders et al. Sept. 5, 1950 2,728,682 Kalinowski et al. Dec. 27, 1955 FOREIGN PATENTS 149,419 Australia Dec. 15, 1952 

1. AN ADDITIVE PRACTICALLY FREE OF AMIDO GROUPS SUITABLE FOR USE IN BITUMEN COATING MATERIAL, PREPARED BY REACTING FOR A PERIOD OF FROM ABOUT 1/4 TO ABOUT 1.0 HOUR AT A TEMPERATURE WITHIN THE RANGE OF FROM ABOUT 180*F. TO ABOUT 240*F. A MIXTURE OF ALKANOL MONOAMINES AND ALKYLENE POLYAMINES HAVING FROM 2 TO ABOUT 6 AMINO GROUPS PER POLYAMINE MOLECULE, SAID MIXTURE CONSISTING ESSENTIALLY OF FROM ABOUT 75% TO ABOUT 95% BY WEIGHT OF AT LEAST ONE ALKYLENE POLYAMINE CONTAINING AT LEAST ONE PRIMARY AMINO GROUP AND FROM ABOUT 5% TO ABOUT 25% BY WEIGHT OF AT LEAST ONE ALKANOL MONOAMINE, THE ALKANOL GROUPS OF WHICH CONTAIN FROM 2 TO 4 CARBON ATOMS, WITH SUBSTANTIALLY DEHYDRATED "EBONY FAT", THE TOTAL OF AMINES PLUS ALKYLOLAMINES CONTACTED WITH SAID "EBONY FAT" BEING IN EXCESS OF THE STOICHIOMETRIC REQUIRE. MENT FOR REACTION WITH SAID "EBONY FAT", 